New research from Perth's Telethon Institute for Child Health Research has revealed an unexpected pattern in the rate and incidence of type 1 diabetes amongst children in Western Australia, adding to evidence that environmental factors could have a major influence on the disease.
The study, published in the journal Diabetes Care, shows that mini epidemics of the disease have been occurring in five yearly cycles in Western Australia over the past 25 years.
The research team analysed every new case of Type 1 diabetes in WA between 1985 and 2010. The study showed the rate of the disease has increased by more than two per cent per year over that period. In some cases there was a 20 per cent difference in the rate of the disease between a low incident and high incident year.
Study co-author Professor Tim Jones said that the pattern adds to current thinking that environmental factors may have a key role to play in the onset of the disease.
"We don't really know what the triggers are, however the work we have done has shown that more children were diagnosed with type 1 diabetes during the cooler autumn and winter months so we do believe changing climate and cyclical weather patterns may play a role along with the changing incidence of viral infections." said Professor Jones.
The study also uncovered some striking similarities between the rate and occurrence of type 1 diabetes in Western Australia and that in parts of Northeast England.
"We're looking at two very different countries with different populations and climates, yet the pattern of type 1 diabetes is almost identical." said Professor Jones. "Our challenge now is to find out why?"
"There is some speculation that the peaks could be linked to times where particular viruses are dominant, but we now need to undertake much more research to determine the factors that are at play here."
The study shows that with previous peaks occurring in 2002 and 2007 another peak would be expected to show up in collected data this year.
Read the abstract: Cyclical Variation in the Incidence of Childhood Type 1 Diabetes in Western Australia (1985-2010)